Towable aerovehicle system with automated tow line release

ABSTRACT

An unmanned, towable aerovehicle is described and includes a container to hold cargo, an autogyro assembly connected to the container and to provide flight characteristics, and a controller to control operation the autogyro assembly for unmanned flight. The container includes a connection to connect to a powered aircraft to provide forward motive force to power the autogyro assembly. In an example, the autogyro assembly includes a mast extending from the container, a rotatable hub on an end of the mast, and a plurality of blades connected to the hub for rotation to provide lift to the vehicle. In an example, an electrical motor rotates the blades prior to lift off to assist in take off. The electrical motor does not have enough power to sustain flight of the vehicle.

This application claims the benefit of U.S. Provisional Application No.61/180,813 filed on May 22, 2009, entitled “Towable Air Vehicle.”

FIELD

The present disclosure related to an aerovehicle, and more particularly,to an unmanned autogyro.

BACKGROUND

An autogyro aircraft is piloted by a person and derives lift from anunpowered, freely rotating rotary wing or plurality of rotary blades.The energy to rotate the rotary wing results from the forward movementof the aircraft in response to a thrusting engine such as an onboardmotor that drives a propeller. During the developing years of aviationaircraft, autogyro aircraft were proposed to avoid the problem ofaircraft stalling in flight and to reduce the need for runways. Therelative airspeed of the rotating wing is independent of the forwardairspeed of the autogyro, allowing slow ground speed for takeoff andlanding, and safety in slow-speed flight. Engines are controlled by thepilot and may be tractor-mounted on the front of the pilot orpusher-mounted behind the pilot on the rear of the autogyro. Airflowpassing the rotary wing, which is tilted upwardly toward the front ofthe autogyro, provides the driving force to rotate the wing. TheBernoulli Effect of the airflow moving over the rotary wing surfacecreates lift.

U.S. Pat. No. 1,590,497 issued to Juan de la Cierva of Madrid, Spain,illustrated a very early embodiment of a manned autogyro. Subsequently,de la Cierva obtained U.S. Pat. No. 1,947,901 which recognized theinfluence of the angle of attack of the blade of a rotary wing. Theoptimum angle of attack for the blades or rotary wing was described byPitcairn in U.S. Pat. No. 1,977,834 at about the same time. In U.S. Pat.No. 2,352,342, Pitcairn disclosed an autogyro with blades which werehinged relative to the hub.

Even though the principal focus for low speed flight appears to haveshifted to helicopters, there appears to have been some continuinginterest in autogyro craft. However, development efforts appear to havelargely been restricted to refinements of the early patented systems.For instance, Salisbury, et al., U.S. Pat. No. 1,838,327, showed asystem to change the lift to drag response of a rotary wing.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a side view of an aerovehicle according an example of thepresent invention;

FIG. 2 is a top view of an aerovehicle according an example of thepresent invention;

FIG. 3 is a front view of an aerovehicle according an example of thepresent invention;

FIG. 4A is a schematic view of components of an aerovehicle according toan example of the present invention;

FIG. 4B is a schematic view of components of an aerovehicle according toan example of the present invention;

FIG. 5A is a schematic view of a controller for the aerovehicleaccording to an example of the present invention;

FIG. 5B is a schematic view of a controller and sensor assembly for theaerovehicle according to an example of the present invention;

FIG. 6 is a schematic view of an aerovehicle during takeoff according anexample of the present invention;

FIG. 7 is a schematic view of an aerovehicle during flight according anexample of the present invention;

FIG. 8 is a schematic view of an aerovehicle during release according anexample of the present invention;

FIG. 9 is a schematic view of an aerovehicle during landing according anexample of the present invention;

FIG. 10 is a view of an aerovehicle with a propulsion system accordingan example of the present invention;

FIG. 11 is a flow chart of an aerovehicle method according an example ofthe present invention;

FIG. 12 is a flow chart of an aerovehicle method according an example ofthe present invention;

FIG. 13 is a flow chart of an aerovehicle takeoff flight control methodaccording an example of the present invention; and

FIG. 14 is a flow chart of an aerovehicle landing method according anexample of the present invention.

DETAILED DESCRIPTION

The present inventors have recognized the need for more efficientdelivery of cargo. Modern commerce and military plans require efficientdelivery of needed supplies, equipment, and parts. However, air deliveryis limited by the weight and bulk that a given aircraft can carry. Forexample, a Cessna 172 with a single pilot can carry a payload of 400 lb.or 30 cubic feet; a Cessna 182 with a single pilot can carry a payloadof 500 lb. or 32 cubic ft.; a Caravan 650 Super Cargomaster with a twopilot can carry a payload of 2,500 lb. or 451 cubic ft. Helicopters alsohave limited cargo capacity: a Robinson 44 with a single pilot can carrya maximum payload of 500 lb. in 25 cubic ft.; a Robinson 22 with asingle pilot can carry a maximum payload of 200 lb. in 16 cubic ft.; aBell 206B with a single pilot can carry a maximum payload of 700 lb. in30 cubic ft. Much of a helicopter's cargo capacity, either weight orvolume, is taken up by a heavy engine, heavy transmission, tail rotorassembly, etc. Moreover, such a delivery method is expensive asoperating costs of a manned aircraft are quite high. With the aboveproblem recognized, the inventors developed an unmanned aircraft thatcan deliver cargo in an efficient manner, e.g., more inexpensive pertrip, per weight, and/or by volume. A towable aerovehicle was developed,by the present inventors, that includes an autogyro, and hence its ownlift. The aerovehicle can act as a trailer to a powered aircraft. Thepresent vehicle can carry cargo that is at least 100% of the volume thatthe towing aircraft can carry. Examples of the presently describedvehicle can further carry about 75% or more of the weight of the cargoof the towing aircraft.

Using autogyro technology with an on-board automated control system, thevehicle can fly safely behind a towing aircraft. In an example, thecontrol system can automatically land the vehicle. In another example,the control system can sense various flight and aerovehiclecharacteristics and automatically control the settings of theaerovehicle, including the autogyro for different phases of flight,e.g., takeoff, towed flight, free flight, and landing.

In an aspect of the present invention, an aerovehicle includes threecomponents, namely, a container to hold cargo, an autogyro assemblyconnected to the container and to provide flight characteristics, and acontroller to control operation of the autogyro assembly for unmannedflight, which can include at least one of takeoff, towed flight, freeflight, and landing. The container includes a connection that connectsto a powered aircraft, which provides forward motive force to power theautogyro assembly. In an example, the autogyro assembly includes a mastextending from the container, a rotatable hub on an end of the mast, anda plurality of blades, connected to the hub, for rotation to providelift to the vehicle. The autogyro assembly can include a rotor shaftposition sensing system. In an example, an electrical pre-rotor rotatesthe blades prior to lift off to assist in take off. The electricalpre-rotor does not have enough power to sustain flight of the vehicle inan example. The container supports sensor systems that can be adapted toindicate load, weight and balance of the cargo supported by thecontainer. In an example, the sensor system can be an airspeed indicatorsensor. The sensor system can include a position sensing system. Thesensor system can include Pitot sensors, which sense the air speed.

The controller can sense various flight characteristics and process thesensed data to control the rotational speed of the hub or blades, angleof attack of the hub and plurality of rotating blades, and the pitch ofthe blades. In an example, the controller senses forward motion, e.g.,velocity or acceleration, to control the autogyro assembly. In anexample, the controller can receive signals from remote transmitters,e.g., a land based transmitter or from the towing aircraft. Thecontroller can adjust components of the autogyro assembly using thereceived signal. In an example, the controller outputs blade pitchcontrol signals to operate actuators that set the angle of blades. In anexample, the controller outputs control signals to operate actuatorsthat control the position of at least one of vertical stabilizers andhorizontal stabilizers.

The container encloses a volume within a body to hold cargo. The body isdefined by a frame on which a skin is fixed. An undercarriage isprovided that contacts the ground for landings and takeoffs. A rearstabilizer is provided to improve the flight characteristics of theaerovehicle. In an example, the undercarriage includes a trolley thatcontacts the ground to provide mobility and is removable from rest ofthe container.

FIGS. 1, 2, and 3A show a side view, a top view, and a front view of anunmanned aerovehicle 100. The unmanned aerovehicle 100 is an autogyrovehicle that flies based at least in part on the lift created byrotating airfoil blades. The operating principal is the same as a fixedwing airplane with the airfoil blades rotating. The aerovehicle 100includes an undercarriage 103 on which is supported a container 105 andautogyro assembly 110. The undercarriage 103 is to contact the groundand support the container 105. The undercarriage 103 as shown includes aframe 111 on which are mounted mobility devices 113 that contact theground and allow the vehicle 100 to move on the ground. The mobilitydevices 113 can include wheels, pontoons, and/or skis (as shown). Theframe 111 supports the container 105. In a further example, theundercarriage 103 is releasably mounted to a trolley on which is mountedmobility device(s). The undercarriage 103 can further include aplurality of supports 114, e.g., cross members at the front and rear ofthe container 105 from which legs extend downwardly from the container.The mobility devices 113 are fixed at the downward ends of the legs.Supports 114 can include sensors 115 that measure the weight ordisplacement at each of the legs. Sensors 115 communicate the senseddata to the controller, e.g., controller 401.

The container 105 is shown as an enclosed body 120 that defines aninterior volume in which cargo can be stored. In an example, thecontainer 105 includes a platform on which cargo is stored. The body 120can be fabricated out of wood, composites, carbon fiber, plastic,polymer or lightweight metal. These rigid materials can form a frame onwhich a skin is fixed. The wood body can be a limited use body, e.g.,one-time use. The container 105 can have a high strength internal framewith a lightweight skin fixed thereto. The skin can be a fabric, a thinplastic, a carbon fiber fabric, or a thin, lightweight metal skin. Theenclosed body 120 has essentially smooth outer surfaces and a narrowed,leading nose 122. The body can further be a monocoque design, wherebythe external skin supports the structural load. In an example, the bodyhas a semi-monocoque design in which the body is partially supported bythe outer skin and can have some frame elements that also support thestructural load. The body 120 can further include doors that can beopened for loading and securely closed during flight. The doors can bepositioned on the sides, in the nose, or in the tail.

A stabilizer system 126 is on the body 120 to assist in flight. Here asshown, the stabilizer system is a rear stabilizer. The rear stabilizer126 includes a central horizontal tailplane 127, which can include anelevator that is moveable vertically by an actuator, which is controlledby the controller, and a vertical fin 128 is mounted to a respective endof the tailplane 127. The vertical fins 128 can be fixed. In an example,the vertical fins 128 are connected to actuators 129 that move thevertical fins horizontally in response to signals from the controller.The horizontal tailplane 127 is spaced from the rear of the body 120such that a gap is between the rearward edge of the body 120 and theleading edge of the tailplane 127. It will be recognized that thestabilizer system 126 can be shaped or designed to better stabilize thevehicle based on the various shapes of the body, loads it will carry,towing power of the towing aircraft, and turbulence. The stabilizersystem 126 can be positioned to best aid in stable flight of the vehicle100. In various example, the stabilizer system can include a T-tail,J-tail, V-tail, cruciform tail, twin tail, among others.

In an example, a container 105 that can be towed by Cessna 172, SuperCub, or other similar aircraft can hold about 1,000 lbs (+/−100 lbs.) ofcargo in a volume of about 154 cubic ft. (+/−10 cubic feet). The cargovolume of the container store cargo of a maximum length of about 12 ft.(+/−one foot). In this example, the body 120 has a length, nose to rearof 18.5 feet and a height of 5 feet. The rear stabilizer 126 extendspartly onto the body and is attached thereto by a plurality ofconnections on each of the vertical fins 128. The rear stabilizer 126adds about two feet onto the length of the vehicle.

The container 105 further includes a connection 150 at which a tow line(not shown in FIG. 1, 2, or 3A) can be attached so that a tug aircraftcan provide motive force to the vehicle 100. In an example, theconnection 150 can be a glider tow connection. Examples of a glider towconnection can be found in U.S. Pat. Nos. 2,425,309; 2,453,139;2,520,620; and 2,894,763, which are incorporated herein by reference forany purpose. However, if any of these incorporated patents conflict withany of the present disclosure, the present disclosure controlsinterpretation. One example of a tow connection 150 is a hook mounted onthe front of the vehicle 100, e.g., on the container 120 or the frame103. A similar connection can be on the rear of the tug or towingaircraft. In an example, the hook is on the bottom of the tug aircraft,e.g., on the tailwheel structure or on the bottom of the fuselage.Examples of the hook include a Schweizer hitch, a Tost hitch, and anOttfur hook. The hook is to hold an end of the tow line, for example, aring fixed to an end of the tow line. On the tug aircraft the hook isopen toward the front of the aircraft and the ring and tow line extendrearward from the tug aircraft. A release mechanism allows a person inthe aircraft to release the ring from the hook by moving the hook sothat it opens from the tow position to a release position such that thehook is open more rearward than in the tow position. The releasemechanism can be linkage connected by a release line to the pilot whocan change position of the hook by moving a lever connected to therelease line. The same mechanisms, e.g., hook, and release mechanism,are mounted on the vehicle 100. The hook on the vehicle 100 is openrearward so that the tow line is secure during flight.

The tow line and/or the rings can have a weak link that will fail if theforces between the vehicle and the tug aircraft are too great. Theseweak links are designed to fail and release the vehicle 100 if a forcebetween the tug aircraft and the vehicle may result in catastrophicfailure for either the vehicle or the tug aircraft. In the event of aweak link release of the aerovehicle from the towing aircraft, thecontroller on board the aerovehicle and execute flight instructions,which can be stored in on-board memory, to fly the vehicle 100.

The tow line between the tug aircraft and the vehicle 100 can provideelectrical transmissions, e.g., electrical power, from the tug aircraftto the vehicle 100. In an example, the tow line can further providebidirectional communication between the tug aircraft and the vehicle100, in particular to the vehicle controller.

The autogyro assembly 110 is fixed to a central location on the body105. The autogyro assembly 110 includes an upwardly extending mast 130.A hub 132 is rotatably mounted on the upward end of the mast 130. Thehub 132 supports a plurality of blade supports 134 on which airfoilblades 135 are mounted. The blades are shown in FIG. 1 and not FIGS. 2and 3 for clarity. The blades 135 can be manufactured from aluminum,honeycombed aluminum, composite laminates of resins, fiber glass, and/orother natural materials, and/or carbon fiber. The blade supports 134,and hence, blades, are provided in opposed pairs. In an example, theblades are an equal number of opposed pairs of blades. In an example,the number of blades is four (two pairs of opposed blades). In anexample, the blades can be of any number of blades that are equallyspaced in the plane of rotation. In an example, three blades areprovided and are spaced about 120 degrees from each other. The airfoilblades 135 have a cross sectional shape that resembles an airplane wingto provide lift during flight. The autogyro assembly 110 includesactuators that control the rotational position of the blades 135.Stanchions or guide wires 137 extend from the body 105 to the top of themast 130 to stabilize the mast during flight and from the forces exertedthereon by the rotation of the hub 132 and blades 135.

The airfoil blades 135 can be retracted to be adjacent the hub orremoved from the hub 132 for further transport of the vehicle orrecovery of at least some components of the vehicle. Examples of furthertransport can include sailing the vehicle on a boat, loading the vehicleon a truck, or loading the vehicle inside an airplane. In an example,the airfoil blades 135 are removed, as desired, from the hub 134. Theairfoil blades 135 can be unitary and single elongate bodies. Thesebodies can be made from metal, natural composites, wood, carbon fiberlayers, resins, plastics, or semisynthetic organic amorphous solidmaterials, polymers, and combinations thereof. The blades 135 can thenbe transported back to an airfield and reused on a different autogyroassembly. In an example, the blades 135 from a plurality of vehicles arestored in one of the vehicles for a return flight from its missionlocation to a home airfield. In this example, only one of the vehicles100 need be flown from its destination to retrieve the more costly partsof other vehicles. Other components such as the controller, sensors, andhub can also be removed from vehicles that will not be recovered andstored in a vehicle that will be recovered.

In an example, the airfoil blades 135 are foldable such that they havean extended position for flight and a retracted position for non-flight.An example of retractable airfoil blades is described in U.S. PatentPublication No. 2009/0081043, which is incorporated herein by referencefor any purpose. However, if U.S. Patent Publication No. 2009/0081043conflicts with any of the present disclosure, the present disclosurecontrols interpretation. Thus, during ground transportation or duringother non-flight times the blades 135 are retracted such that theairfoil blades do not interfere with ground crews or experience forceson the blades during ground movement.

The airfoil blades 135 have at least one section that has an airfoilprofile. This section of the blade 135 has a shape when viewed incross-section that has a rounded leading edge and a sharp, pointedtrailing edge. A chord is defined from the leading edge to the trailingedge. The chord asymmetrically divides blade into an upper camber and alower camber. The upper camber is greater than the lower camber.Moreover, the upper and lower cambers can vary along the length of thesection and entire airfoil blade. The airfoil blade moves through theair and the passage of air over the blade produces a force perpendicularto the motion called lift. The chord defines the angle of attack forthat section of the blade. The angle of attack can be defined as theangle between the chord and a vector representing the relative motionbetween the aircraft and the atmosphere. Since an airfoil blade can havevarious shapes, a chord line along the entire length of the airfoilblade may not be uniformly definable and may change along the length ofthe blade.

FIG. 4A shows a schematic view of the autogyro assembly 110, whichincludes the mast 130, hub 132, blade supports 134, and airfoil blades135. The autogyro assembly 110 further includes a controller 401, anelectrical motor 403, a plurality of actuators 405, and a power source410 connected to each device in need of electrical power. The controller401 is in communication with the electrical motor 401 and actuators 405to control operation thereof. The controller 401 can further communicatewith sensors 412 to receive performance data that can be used to controlcomponents of the autogyro assembly. In an example, the controller 401controls operation of various moveable components such that the vehicle100 flies unmanned. In this example unmanned means that there is nohuman being on board the vehicle 100 to control flight of the vehicle100. The controller 401 can further control flight of the vehicle 100being towed by another aircraft.

The controller 401 can control operation of the electrical motor 403that rotates a drive shaft connected to the hub 132 to rotate theairfoil blades 135. The motor 403 adds rotational power to the rotorsystem to reduce drag and assist in the lift provided by the airfoilblades 135. This can help the vehicle 100 achieve flight. The motor 403,in an example, does not provide sufficient power to sustain flight ofthe aerovehicle 100. In an example, the motor 403 can provide sufficientpower to the rotating airfoil blades 135 such that the vehicle 100 canlaunch the vehicle in a cargo-free state. The motor 403 can furtherprovide rotational power that can be used to reduce blade angle ofattack, prevent rotor decay of RPM speed, improve landing glide slopeand decrease the decent speed. These features may be described ingreater detail with regard to operational of the vehicle, e.g. FIGS.6-9.

The controller 401 controls operation of the actuators 405, whichcontrol the tilt of the airfoil blades 135. During prerotation of theblades 135 prior to takeoff, the actuators 135 hold the blades in a flatposition that has a very low angle of incidence, e.g., 0 degrees, lessthan 5 degrees, or less than 10 degrees. Prerotation is the rotation ofthe airfoil blades prior to take off or rotation of the blades by theonboard motor. Once the blades 135 are at a desired rotational speed,the actuators 405 can drive the blades to a takeoff position with anangle of incidence greater than the prerotation, flat position and aflight position. Once the vehicle 100 is in flight, the actuators 405can reduce the angle of incidence relative to the takeoff angle to theflight position. The flight position of the actuators 405 and blades 135is greater than the prerotation position. In another example, theactuators 405 release the blades 135 during flight so they can find theoptimum angle of incidence without influence by the actuators 405.

In a flight profile of the vehicle 100, the flat, prerotation positionof the blades 135 results in a zero angle of incidence to reduce drag onthe blades during prerotation such that a smaller motor and power sourcecan be used. At takeoff, the blades 135 are set at an angle of incidenceof about 12 degrees. Each of the degree measurements in this paragraphcan be in a range of +/−one degree. During flight, the blades 135 areset at an angle of incidence of about 5 degrees. During the approach,the blades 135 are set at an angle of incidence of about 12 degrees.During the landing the blades 135 are set at an angle of incidence ofabout 20 degrees or more.

The aerovehicle 100 can result in a 50% increase or more in cargocapacity relative to the towing aircraft. In an example, the vehicle 100can tow about half of the gross weight of the towing aircraft. In someexamples, the aerovehicle 100 results in a 75% to 100% increase in cargocapacity with cargo capacity measured by weight. A further benefit isthe aerovehicle having a body that can hold larger, either in length,width, or height than the towing aircraft as the vehicle 100 does nothave all of the design constraints that a manned aircraft must have.

An actuator 420 is connected to the mast 130 to move the mastlongitudinally and laterally to correct for unbalanced loads in thecontainer. In an example, there is a plurality of actuators 420, whichcan be screw jacks that are electrically powered. Load sensors, e.g.,sensors 115, sense the deflection of container on the frame and feedthis data to the controller 401. The controller 401 calculates the loadpositioning, including empty weight (for different vehicle 100configurations) and center of gravity. The controller 401 can indicateto the ground crew how much more cargo, by weight, the vehicle cansafely fly. The controller 401 further calculates the center of gravitybased on data from the load sensors. The controller can engage theactuator(s) 420 to move the autogyro assembly 110 forward and aft, andleft or right to keep the mast and hub, and hence the point of rotationof the blades, as close to the center of gravity as possible. In anexample, the actuators 420 are jack-screws that precisely position themast 130. If the autogyro assembly 110 cannot be moved to sufficientlyto center the autogyro assembly 110, e.g. mast and hub, at the center ofgravity, then the controller 401 will issue an error message to theground crew. Messages to the ground crew can be displayed on videodisplay 510, stored in memory 504 or 506 or sent view network interfacedevice 520 over a network 526 to other devices, e.g., handheld devices,for display.

Referring now to FIG. 4B, an example hub 132 is shown that includes amain body 450 that includes top 452 that defines an opening in which theairfoil blades 136 or blade supports 134 are fixed. Shock bumpers 455engage the top of the airfoil blades 136 or blade supports 134 in thebody 450 to prevent mast bumping. In an example, the body 450 is fixedto a drive gear 457 that can be engaged by the motor 403 through a driveshaft 458 or manually to rotate the hub body 450 and the blades attachedthereto. In another example, the main body 450 is fixed on a universaljoint 460 that can be fixed to a drive shaft that extends in the mastfrom the motor 403 to the hub 132. In another example, the main body 450and drive gear 457 rotate on the joint 460. The joint 460 allows themain body 450 to be tilted vertically such that the airfoil blade istilts downwardly from the front to the back to create and angle ofincidence. An actuator 480 controls the amount of tilt of the airfoilblades. The controller 401, based on its application of its stored rulesand the sensor inputs, sends signals to the actuator 480 to control theangle of incidence of the airfoil blades. In an example, the actuator480 is positioned at the front of the hub 132. Thus, the actuator 480controls the pivot of the hub on axis 482.

FIG. 5A shows an example of the controller 401 within which a set ofinstructions are be executed causing the vehicle 100 to perform any oneor more of the methods, processes, operations, or methodologiesdiscussed herein. In an example, the controller 401 can include thefunctionality of the computer system.

In an example embodiment, the controller 401 operates as a standalonedevice or may be connected (e.g., networked) to other controllers. In anetworked deployment, the one controller can operate in the capacity ofa server (master controller) or a client in server-client networkenvironment, or as a peer machine in a peer-to-peer (or distributed)network environment. Further, while only a single controller isillustrated, the term “controller” shall also be taken to include anycollection of devices that individually or jointly execute a set (ormultiple sets) of instructions to perform any one or more of themethodologies discussed herein.

The example controller 401 includes a processor 502 (e.g., a centralprocessing unit (CPU) or application specific integrated chip (ASIC)), amain memory 504, and a static memory 506, which communicate with eachother via a bus 508. The controller 401 can include a video display unit510 (e.g., a liquid crystal display (LCD) or a cathode ray tube (CRT)).The controller 401 also includes an alphanumeric input device 512 (e.g.,a keyboard), a cursor control device 514 (e.g., a mouse), a storagedrive unit 516 (disk drive or solid state drive), a signal generationdevice 518 (e.g., a speaker), and an interface device 520.

The drive unit 516 includes a machine-readable medium 522 on which isstored one or more sets of instructions (e.g., software 524) embodyingany one or more of the methodologies or functions described herein. Thesoftware 524 can also reside, completely or at least partially, withinthe main memory 504 and/or within the processor 502 during executionthereof by the controller 401, the main memory 504 and the processor 502also constituting machine-readable media. The software 524 can furtherbe transmitted or received over a network 526 via the network interfacedevice 520.

While the machine-readable medium 522 is shown in an example embodimentto be a single medium, the term “machine-readable medium” should betaken to include a single medium or multiple media (e.g., a centralizedor distributed database, and/or associated caches and servers) thatstore the one or more sets of instructions. The term “machine-readablemedium” shall also be taken to include any medium that is capable ofstoring, encoding or carrying a set of instructions for execution by acomputer or computing device, e.g., controller 401, or other machine andthat cause the machine to perform any one or more of the methodologiesshown in the various embodiments of the present invention. The term“machine-readable medium” shall accordingly be taken to include, but notbe limited to, solid-state memories, optical and magnetic media, andcarrier wave signals.

The interface device 520 is further configured to receive radiofrequency signals. These signals can trigger certain operations to becommanded by the controller 401. In an example, a signal can be sentfrom the motive unit, e.g., an airplane or a helicopter, and received bythe interface device 520.

The controller 401 executes flight control instructions without the needfor an on-board pilot. The controller 401 includes multiple flight rulesfor different phases of flight, i.e., takeoff, cruise, unaided flight,and landing phases. The controller 401 controls the pitch for each ofthese different phases by data from the sensors and applying this datausing the flight control instructions. Pitch is the position of theplane in which the blades travel relative to a horizontal plane(essentially parallel to the ground).

The controller 401 can further store data and instructions forautonomous return flight. The controller 401 can store the weight ofvehicle 100 absent cargo. As the cargo can be up to about 80% of thegross weight of the vehicle 100 during a delivery flight, it isenvisioned that the motor 403 may be able to rotate the blades 135 toachieve take-off. In an example, the vehicle 100 is positioned so thatit faces into a headwind. The headwind provides a relative forwardwindspeed against the airfoil blades 135. The controller 401 instructsthe motor to rotate the blades and the vehicle can be airborne. Anotherexample of self flight is described below with reference to FIG. 11,which can be used in conjunction with the present example. Onceairborne, the controller 401 can sense the position of the vehicle 100,for example, using a global navigation satellite system (GNSS) such asGlobal Positioning System (GPS), Beidou, COMPASS, Galileo, GLONASS,Indian Regional Navigational Satellite System (IRNSS), or QZSS. Thenavigational system can include a receiver that receives differentialcorrection signals in North American from the FAA's WAAS system.

FIG. 5B shows an example of a flight system 530, which includes acontroller 401 in communication with a data base 516 and a communicationsystem 590. A plurality of sensors are to sense various flight datainputs and communicate the sensed data to the controller 401 forprocessing using the processor or for storage in the database 516. Asdescribed herein the controller 401 includes processor 502 and localmemory 504. Database 516 is protectively mounted with the controller ina black box that secures the database and processor from harm duringtakeoffs, landing, non-authorized intrusions, and unscheduled landings.The database 516 can include a cartography database 531 that stores theterrain information that is or could be part of the vehicles flightpath. The cartography database 531 can store data relating to physicaltraits, including but not limited to roads, land masses, rivers, lakes,ponds, groundcover, satellite imagery or abstract data including, butnot limited to, toponyms or political boundaries. Encryption rules anddata 533 can also be stored in the database. Flight rules 535 are storedin the database. The processor 502 can access the cartography database531, encryption rules or data 533, and other stored rules 535 tocalculate a desired flight path and or correct for various obstacles orflight path deviations.

The controller 401, and in an embodiment the processor, can invokevarious rules that can be stored in a memory and read by the controller.The loading of these flight rules sets the controller 401 to a specificmachine. In an example, the controller 401 checks the “if, and, or” filefor altitude restrictions, obstacles, restricted space during theplanning phase. As used herein a file is code that can be stored in amachine readable form and transmitted so as to be read and loaded intothe controller 401. During the “Takeoff, In Flight and Landing” phasesthe controller checks the flight sensor package including but notlimited to: rotor rpm sensor, rotor disk angle of attack sensor, load onwheels sensors, tow bridle angle horizontal and lateral position sensor,tow bridal load % rating, horizontal stabilizer angle and trail positionsensors.

Additional control rules and instructions include waypoint takeoff rulesthat result in the present position, e.g., as GPS grid coordinates,being entered into and stored in the controller 401. In an example, atleast one waypoint is entered into the controller 401. In an example,additional waypoints are entered. Any number of waypoint coordinates canbe entered. These waypoints generally define the flight path for theaerovehicle 100. Alternate flight path waypoints can also be stored inthe controller 401. Separate waypoints can be stored for the landingsequence. Known obstacles along the intended flight path (as can bedefined by the waypoints) can be stored in the controller for eachstored flight path and landing path. The controller 401 uses storedflight route (e.g., path), weight of the aerovehicle as indicated by thelanding gear load sensors or determined by an external scale, and flightdata entered by the mission planning computer to recommend route changesto maintain the recommended vertical separation and ground clearancerequirements. In an example, the mission planning computer can calculatethese route changes and download them to the controller 401.

The controller 401 is connected to a takeoff sensor that senses when theload is removed from the landing gear sensor. The controller 401 thancan change from a takeoff setting to a flight setting. The controllercan delay the change to a flight setting until a certain altitude isreached. The controller 401 is also connected to a forward air speedthat can indicate when never exceed velocity (V_(NE)) is achieved orwhen a stall velocity is being approached. If a stall velocity isimminent, the controller 401 can release the tow line if still attachedto the tow aircraft. The controller 401 can also receive data relatingto the rotor's revolution speed (e.g., RPM). In an example, thecontroller 401 receives this data and can calculate the currentrevolution speed as a percentage of maximum speed. If the maximum speedis reached, the controller 401 can instruct a brake system to slow therotor speed. The controller can also act based on the rotor speed beingtoo low, e.g., start the pre-rotor motor, release the tow line,calculate an emergency landing, etc. An emergency landing calculationcan use the navigational system coordinates, stored maps (includingpopulation centers), requests for more information, calculation of adescent path, etc. The controller 401 can also receive data relating tooperation of an actuator to control a rotor disk angle of attack exceedan operational threshold, e.g., retraction or extension at a given rate(e.g., % per second).

The controller 401 can further receive data from a forward flight sensorand tracking controls. The data can include at least one of: forwardspeed from which a percent (%) of flight speed can be calculated; rotordisk angle of attack (e.g., from a mast sensor); tow angle of a bridle(to which the tow line is connected), which can be used to determine thealtitude difference relative to the towing aircraft; a lateral angle ofthe bridle (e.g., left and right of 180° line along the center line ofthe towing aircraft and aerovehicle).

The controller 401 can also receive data relating to the stabilizersystem, which data can include position (extension and contraction) ofstabilizer component actuators. The controller can use this data to holdthe aerovehicle at a certain position (with a few degrees) behind thetow aircraft.

The controller 401 further uses sensed data for its flight rules relatedto a landing sequence. The landing sequence data can include but is notlimited to actual forward airspeed from sensors, from which speedincrease and decrease as well as position can be determined by thecontroller. The controller 401 can also receive data relating to whetherthe connection to the tow aircraft (e.g., the tow line) has beenreleased. The controller 401 can receive data relating to rotor diskangle of attack to maintain bridal tension and vertical position. Whenin free flight the controller 401 can monitor the flight speed and oncethe bridal, e.g., the tow line, is release, then the ground radar on theaerovehicle is activated. Using the ground radar or the forward velocitythen controller 401 can autonomously control the position of the rotordisk (e.g., blade) angle actuator to control the position of the blades.Near the ground, e.g. within 100 feet or within 20 feet of the ground,the controller further increases the rotor disk (e.g., blade) angle. Theincrease in the rotor disk angle need not be linear and can increasefaster as the ground approaches based on both the speed (decent andforward) and the distance to the ground. In an example, the controllerfurther has the pre-rotor motor add power to the rotating bladesimmediately before the landing gear touches the ground. The controllercan further use data from the load sensors to sense when touchdownoccurs as the load will increase on these sensors at touchdown. Whentouchdown occurs, the controller 401 will cut power to the pre-rotormotor. The controller 401 can engage rotor brakes and or landing gearbrakes. In an example, the controller 401 can autonomously perform, oneor more of the preceding functions.

A communication system 520 is in communication with the controller 401and is adapted to communicate with other devices outside the aerovehicle100 for remote communication 580. The remote communication 580 can bewith other vehicles 100, the tow aircraft, or with ground basedcommunication devices. Accordingly, real time external data and commandscan be received by the controller 401 and flight performance can bealtered by the controller interpreting this data and/or commands togenerate control signals to controllable components in the aerovehicle.

The sensors 541-549, 551 can be adapted to sense various data thatrelate to performance of the aerovehicle 100 and electricallycommunicate the sensed data to the controller. The sensors 541-549, 551can send raw sensor data to the controller 401 for interpretation. In anexample, the sensors 541-549, 551 include processing circuits thatinterpret the raw data into data that can be used by the controllerwithout further processing. A weather data source 541 senses variousweather conditions, including visibility, rain, sun light, cloud cover,cloud height, barometric pressure, among others. In an example, theweather data source 541 is a sensor that senses the weather and can bemounted to the body of the vehicle such that the sensor can senseweather outside the vehicle body. A weight sensor 542 is adapted tosense the weight of the vehicle and can be mounted to at least one partof the frame. In an example, a weight sensor 542 is mounted to each ofthe legs of the vehicle frame to provide data from which the controller401 can determine or derive the vehicle's center of gravity. A satelliteimagery source 543 is adapted to sense satellite imagery data sent tothe vehicle from remote device, such as directly from a satellite. Thuscurrent satellite imagery is available to the controller to make inflight corrections in essentially real time after takeoff. An airspeedsensor 544 senses the airspeed of the vehicle. A power source sensor 545senses at least one of the consumption of power from the power source orthe actual power stored in the power source. The controller can use thepower source data to reduce power consumption if needed to complete theflight plan. An altitude sensor 546 senses the height of the vehicleabove the ground. A vehicle telemetry sensor 547 senses the real-timeposition of the vehicle 100 and can use signals from global navigationsystems. A mast position sensor 548 determines the position of the mast130 of the autogyro assembly 100. The controller 401 can use the mastposition sensor 548 to correctly position the mast 130 within in itsrange of movement in a horizontal plane of movement to position the mastin as close to the center gravity of the loaded vehicle as possible toimprove the flight characteristics of the vehicle. A propulsion sensor551 can sense operation of a motor and propeller in the embodiment wherethe vehicle has a propulsion system.

In operation the controller 401 can use stored data in the database 516with sensed data from sensors 541-549, 551 to control flight of thevehicle when loaded with cargo or while being towed. The controller 401can also operate as an autonomous vehicle return system using the storeddata in the database 516 with sensed data from sensors 541-549, 551 tocontrol flight and return an empty vehicle back to its designated homeposition. In an example, a tow aircraft such as a plane, a vehicle witha propulsion system, a balloon, or other lift devices can provideforward movement such that an empty vehicle 100 can fly on its own orsufficient altitude that a dropping of the empty vehicle will result insufficient forward movement so that the rotating blades provide lift tomaintain the vehicle 100 in flight.

FIG. 6 shows a schematic view of the unmanned aerovehicle 100immediately after takeoff. The aerovehicle 100, which does not havesufficient engine power to fly on its own, is connected to a towaircraft 601, here shown as an airplane, by a tow line 603. Thecontroller sends an instruction so that the motor on board the vehiclebegins rotation of the rotary wing. The rotary wing is rotated to atleast 30% of its desired rotational speed before the towing aircraftbegins its forward movement. In an example, the rotary wing is rotatedup to 50% of its desired flight rotational speed. In some examples, therotary wing is rotated up to 75%, or less than 100% of its desiredflight rotational speed. Once the rotary wing is at a take-off speed,then the towing aircraft 601 can provide the initial propulsion to drivethe vehicle forward such that air flows over the rotary wing, e.g., theblades 135. The vehicle 100 can contain cargo that results in thevehicle 100 having a gross vehicle weight that is up to about the sameas the towing aircraft 601. During takeoff, the cargo body 105 rollsforward on the undercarriage 103, which includes a removable trolleythat has wheels to allow the vehicle 100 to move forward at direction ofthe towing aircraft with an acceptable low resistance such that thetowing aircraft and the aerovehicle can achieve flight. In this example,the rotary wing of the vehicle provides enough lift to achieve flightshortly prior to the ascent of the towing aircraft 601. In theillustrated example, the vehicle 100 leaves the trolley on the ground.The vehicle undercarriage can include further landing devices such aswheels, skis, etc. In an example, the vehicle 100 takes off before thetowing aircraft 601 to establish a flight formation with the vehicle 100at a slightly higher altitude than the towing aircraft 601 at the timeof takeoff.

In an example, the tow line 603 includes, in addition to being amechanical connection between the towing aircraft 601 and theaerovehicle 100, electrical communication lines between the towingaircraft 601 and the aerovehicle 100. In some embodiments, the tow line603 can include any number of ropes (synthetic or natural fibers),cables (metal or polymer), wires, and/or other connective structuresthat are or become known or practicable. In an example, the tow line 603includes a power cable component that is electrically insulated from asignal line and the mechanical component. The tow line 603 can connectan electrical power source on the aircraft 601, e.g., an electricalgenerator or alternator which are driven by the aircraft motor, to thevehicle 100. Both the aircraft 601 and vehicle 100 can include outletsat which the electrical communication line of the tow line 603 isconnected. The tow line 603 can further provide bidirectionalcommunication between the towing aircraft 601 and the controller of thevehicle. The pilot of the tow aircraft 601 can send data and/or commandsto the controller of the vehicle 100. The aircraft 601 can furtherautomatically send data to the controller of vehicle. As a result thesensors on the aircraft can provide additional data that can be used bythe controller, e.g., 401, to control flight of the vehicle 100. In anexample, the controller controls the angle of incidence of the rotatingblades based at least in part on data communicated from the towingaircraft 601. The controller can further take into account data that isreceived from on-vehicle sensors as well.

FIG. 7 shows a schematic view of the unmanned aerovehicle 100 in flightand being towed by the aircraft 601. The aircraft 601 continues toprovide the thrust to move the vehicle 100 through the air such that theair passes over the rotary wing (e.g., airfoil blades 135), whichprovides the lift to the vehicle 100. In flight, the vehicle 100typically flies at a slightly higher altitude than the aircraft 601. Inan example, the vehicle 100 flies at an altitude whereat the turbulencefrom the towing aircraft does not affect the flight of the vehicle 100.The altitude of the towing aircraft 601 can be sent to the vehicle 100over the tow line 603. In an example, the altitude of the towingaircraft can be sent over a wireless connection (e.g., communicationcomponents 520, 580) to the vehicle 100. The control system of thevehicle 100 can then set the altitude of the vehicle based on the datareceived from the towing aircraft 601. In an example, the control system(e.g., controller 401) of the vehicle can receive altitude data fromsensors onboard the vehicle and set the flight altitude based on thisdata. The controller can set the angle of the rotor 701, which changesthe angle of incidence of the airfoil blades by activating actuators tomove the hub and or blades themselves.

The towing aircraft 601 tows the aerovehicle 100 to the landing zone.The tow aircraft 601 tows the aerovehicle 100 over the landing zone. Thesensors onboard the aerovehicle 100 sense various characteristics at thelanding zone. The control system, e.g., controller 401, uses this datato calculate a flight path for landing the vehicle at the landing zone.In an example, the towing aircraft 601 can also sense characteristicsand send the sensed data to the vehicle. In an example, the towingvehicle releases the vehicle 100 prior to the landing zone and thevehicle calculates a flight path based on stored data, such as flightrules and a stored target landing zone, as it approaches the targetlanding zone. The flight path may be stored in the memory of the controlsystem and the controller can change the flight path based on current,sensed data. The vehicle 100 itself may circle the landing zone to havetime to sense ground and flight data. In an example, the vehicle 100includes a ground sensor, such as an imager, a camera, a radio frequencysensor, to determine the condition of the landing zone.

FIG. 8 shows a schematic view of the unmanned aerovehicle 100 after itis released from the tow aircraft 601. Vehicle 100 continues to fly butwill gradually loose air speed and, hence, lift. The stabilization offlight angles (roll, yaw and pitch) and the rates of change of these caninvolve horizontal stabilizers, pitch of the blades, and other movableaerodynamic devices which control angular stability, i.e., flightattitude, horizontal stabilizers and ailerons can be mounted on thevehicle body. Each of these devices can be controlled by the controller.During this free flight, i.e., free from a propulsion device, such asthe airplane or a helicopter, the rotor angle 801 increases. The rotorangle 801 is measured along the plane of rotation of the blades relativeto the plane of the ground. Accordingly, the angle of incidence of theairfoil blades likewise increases.

FIG. 9 shows a schematic view of the unmanned aerovehicle 100 atlanding. The aerovehicle 100 flares at the landing so that is can landwith a near zero forward momentum at the ground. This flaring action iscontrolled by the controller and results in the rotor angle 901 beingfurther increased relative to rotor angles at the takeoff profile angle611 (FIG. 6), the flight profile angle 701 (FIG. 7), and free flightprofile angle 801 (FIG. 8). As shown the rotor angle 901 can be about 45degrees, +/−5 degrees. In an example, the rotor angle 901 is less thanabout 60 degrees, +/−5 degrees. The controller can control the degree offlare at landing depending on the landing conditions. For an example, ifthe vehicle will land on a runway that is suitable for the landing gearon the undercarriage, e.g., wheels on a paved or unpaved prepared runwayor skis on a snow or ice runway, the flare angle may be less than 45degrees and the vehicle will roll to a gentle stop while still havingforward velocity at touchdown for stability. If landing in rough,unprepared terrain, the flare may be severe to reduce the ground roll asmuch as possible to protect the vehicle and landing environment fromdamage. In an example, the aerovehicle 100 can land in a landing zone ofless than 500 feet in length. In an example, the landing zone is lessthan 300 feet in length. In an example, the landing zone is a minimum of50 feet. In an example, the landing zone is a minimum of 100 feet. Thecontroller can land the vehicle in a landing zone that is twice thewidth of the vehicle.

Some applications may require the use of multiple vehicles to be flowntogether. Multiple vehicles can simultaneously deliver equipment andsupplies to remote locations for example for scientific expeditions,military uses, Antarctic expeditions, geological and oceanicexpeditions. Vehicles 100 can be configured so that more than onevehicle can be towed by a single tug aircraft or multiple vehicles 100can be flow by multiple tug aircraft. When in a formation thecontrollers 401 of multiple vehicles can communicate with each other toestablish and maintain a formation. In an example, the plurality ofvehicles can communicate with each other via their respectivecommunication systems 520 (FIG. 5B). The vehicles can maintain a safedistance from each other and, if present, other aircraft. Thecontrollers 401 can make adjustments to the flight control components,e.g., pitch control, vertical stabilizers, horizontal stabilizers, etc.,to maintain the formation. When released from the tug aircraft thecontrollers will control the flight of the plurality of vehicles tosafely land all of the vehicles at the designated target.

Certain components for the vehicle 100 or 1000 can be removed from thevehicle after delivery of the cargo at a landing site. The controller401 is designed as a sealed, black box that can be released from theinterior of the vehicle body. The airfoil blades 135 can be releasedfrom the hub or the blade supports. The hub 132 can also be removed fromthe mast in an example. Any of the sensors 541-549, 551 can be removedfrom the vehicle. Any of the removed components can be packed in anintact vehicle 100 and flown out of the landing site. Thus, the moreexpensive components can be retrieved for later use on other vehiclebodies. This further reduces the cost of cargo delivery in the eventthat it is impractical to return to the landing zone to individuallyretrieve all of the aerovehicles. In an example, up to five vehicles arebroken down with certain components removed and placed in a sixthaerovehicle. This sixth aerovehicle is retrieved using a towing aircraftor is a self-propelled model that flies itself from the landing zone.The controller of the sixth aerovehicle will control the vehicle duringits return flight.

FIG. 10 shows an embodiment of the aerovehicle 1000 with a propulsionsystem 1005. The aerovehicle 1000 can include the same components as theaerovehicle 100 as described herein, including the controller 401,autogyro assembly 110, etc. The propulsion system 1005 includes a motor1010 that drives a drive shaft 1015 that extends outwardly of the bodyof the vehicle 100 to connect to a propeller 1018. A power source 1020is also connected to the propulsion motor 1010 and the controller 401.The motor 1010 can be a low power, e.g., less than 100 horse powermotor. In one specific example, the propulsion system 1005 is designedto be able to provide enough forward movement to the vehicle 1000 sothat the autogyro assembly 110 can provide the lift to the vehicle 1000to achieve and maintain flight. The motor 1010 and propeller 1018 areselected to provide enough forward movement so that there is sufficientair flow over the rotating blades 135 to provide lift to an empty oressentially empty vehicle. Accordingly, the propulsion system 1005 canrecover the vehicle but cannot deliver any heavy cargo. The motor 1010can be a 50 h.p. motor that runs on fuel stored in the power source1020. The fuel can be diesel fuel in an example.

In a further application, the propulsion system 1005 is designed to beable to achieve flight with the vehicle 1000 storing the airfoil blades135 and controllers 401 of at least two other vehicles 100. This allowsthe some components of a fleet of vehicles 100 or 1000 to be retrievedusing a vehicle 1000.

It will further be recognized that the propulsion system 1005 can beused to assist the towing aircraft in pulling the vehicle 1000.Accordingly, the vehicle 1000 can haul more cargo with less input powerfrom the towing aircraft.

If an engine fails in the propulsed aerovehicle 1000, then the forwardmomentum of the aerovehicle 1000 will continue to rotate the rotaryblades and gradually allow the aerovehicle to descend to the ground asthe lift deceases as the relative movement of the air against the rotaryblades decreases. The aerovehicle would slowly descend until landing.

FIG. 11 shows a method 1100 of flight for an aerovehicle 100, 1000 asdescribed herein. At 1102, the controller is powered on. The controllercan then perform various safety checks and check of the operationalcondition of the sensors on board the vehicle. The controller canfurther power the sensors. The controller can check the power status ofthe power source to determine if sufficient power is in the power sourceor will be available to complete a flight. The controller can alsoperform checks of the electronic equipment such as the memory and thecommunication components.

At 1104, the controller requests and stores the flight data for thecurrent flight. The flight data can include data relating to a flightplan including, but not limited to, distance, flight altitudes,estimated time of arrival, landing zone, predicted weather, etc.

At 1106, the aerovehicle is connected to a towing aircraft or to alaunching device. The connection is at least a mechanical connection totransfer power from the towing/launching device to the vehicle. In anexample, electrical connections are also made.

At 1108, the airfoil blades are set to a prerotation position. Theprerotation position is a minimal angle of incidence to reduce drag onthe blades when being rotated. The purpose of prerotation is to assistin the takeoff by overcoming the initial inertial forces in the autogyroassembly in general and specifically on the airfoil blades. Accordingly,the prerotation position of the blades provides minimal, if any, lift.

At 1110, the airfoil blades are rotated. This is the pretakeoff stage.Once the blades are spun up to a desired speed, e.g., revolution perminute, the pretakeoff stage ends.

At 1112, the airfoil blades are set to a takeoff position. The bladesnow have an angle of incidence that can provide lift to the vehicle. Thecontroller can send a signal to actuators to control the position of theairfoil blades. The takeoff position has an angle of incidence greaterthan the prerotation position.

At 1114, the vehicle is moved forward by the towing vehicle or thelaunch device. The forward movement of the vehicle creates airflow overthe airfoil blades that are set to a takeoff position. This airflow overthe rotating airfoil blades creates lift that can achieve flight of thevehicle even when loaded with cargo that could not be flown by thetowing vehicle alone. The controller can set the angle of incidence ofthe airfoil blades to a flight position after the aerovehicle isairborne. The flight position of the airfoil blades has a lesser angleof incidence than the takeoff position.

At 1116, the vehicle is launched and achieves flight as there issufficient airflow over the rotating airfoil blades to achieve flight.The controller can control the flight of the vehicle in response tostored data and rules, sensed data, and received inputs from the towingaircraft, fellow vehicles, or from ground communications. The controllercan set the angle of incidence of the airfoil blades. The flightposition of the airfoil blades has a lesser angle of incidence than thetakeoff position.

At 1118, the vehicle is flown from the takeoff location to the landingzone. The vehicle can be towed to the landing zone by an aircraft. Inanother example, the vehicle is launched and flies itself to landingzone. In an example, the vehicle is towed to a location where it cancomplete the flight to the landing zone on its own. Due to drag andother resistive forces, e.g., friction of the rotating hub, a vehiclewithout a propulsion system will glide to the landing zone. A vehiclewith a propulsion system can fly for a longer time and distance. If thepropulsion system is adequate to provide enough forward thrust so thatthe drag and resistive forces are overcome, the vehicle can fly for asignificant distance albeit at a slow speed.

At 1120, if needed, the vehicle is released from the towing aircraft.The release of the tow line can be in the form of a glider releasemechanism controlled by either the towing aircraft, pilot of the towingaircraft, or by the controller of the aerovehicle. Once released, thecontroller controls flight components of the aerovehicle.

At 1122, the airfoil blades are set to an approach position. Thecontroller controls the position of the airfoil blades. The approachposition has a greater angle of incidence than the flight position. Thiswill provide lift to keep the aerovehicle airborne but bleed off some ofthe forward momentum and velocity to slow the aerovehicle for approach.In an example, the takeoff position and the landing position have theessentially same angle of incidence, e.g., within one degree of eachother.

At 1124, the vehicle automatically flies to the landing zone. Theaerovehicle is in free flight on its own. As a result, the controllersense flight data and issues control signals to controllable components,such as airfoil positions, any rotational damper in the hub or mast, andany moveable component in the tail plane. The controller uses senseddata in flight rules or algorithms to output flight control signals.

At 1126, the airfoil blades are set to a landing position. Thecontroller can issue command signals to actuators to set the angle ofincidence of the airfoil blades. The landing position of the airfoilblades has a greater angle of incidence than the flight position or theapproach position.

At 1128, the vehicle has landed. The controller can no shut down some ofthe consumers of power to save energy in the power source. Thecontroller can further send a status report via the communication systemto a remote receiver, such as a ground station or the towing aircraft.The cargo in the vehicle can now be unloaded. In the event that thevehicle will be retrieved, the controller can indicate that the cargohas been removed by the load sensors indicating that the vehicle is nowat its empty weight. In a further case, other vehicles can be brokendown and stored in another vehicle for retrieval. The controller cansignal that the vehicle loaded with components from other vehicles isready for retrieval. The retrieval sequence of the vehicle is similar tothe method 1100.

In the above method 1100, the airfoil blades have a plurality ofpositions. The prerotation position sets the airfoil blades at an angleof incidence of about zero degrees. The takeoff position has an angle ofincidence of about 12 degrees. The flight position has an angle ofincidence of about five degrees. The decent or approach position has anangle of incidence of about 12 degrees. The landing position has anangle of incidence of about 20 degrees. The present example positionscan vary +/−one degree.

In the above method 1100, the controller can receive guidance signalsfrom ground or air control systems. The air control systems can be froman aircraft that knows an approach envelope and the landing site. Theair control system can send guidance data to the controller onboard theaerovehicle. The guidance data can be on a radio frequency carrier wave.The ground control system can be at a remote location and know theapproach envelope and send guidance data to the controller. In anexample, the ground control system can be at or near the landing zone,e.g., within a mile or within 10 s of miles or within a kilometer orwith 10 s of kilometers. The ground system would then know of hazards atthe landing site that may not be stored in the aerovehicle controller orknown at a remote location. Examples of landing zone hazards are trees,utility lines, rocks, enemies, temporary hazards, etc. The ground systemcan alert the aerovehicle to these hazards or select a new landing zoneor guide the aerovehicle around these hazards. The ground system cansend a radio frequency signal, a microwave signal, or a light/opticalsignal that can be received by the aerovehicle controller.

FIG. 12 shows a method 1200 of flight path calculation for anaerovehicle 100, 1000. At 1202, the controller is powered on. At 1204,the takeoff location is entered. The controller can use on board sensorsto determine its current location and use that location as the takeofflocation. The controller 401 can select from a database containing allnearby airfields. In an example, the takeoff location is downloaded tothe controller. At 1206, a waypoint is entered into the controller. Theway point is a spatial location along the intended flight path of theaerovehicle. The spatial location is a three dimension position of theaerovehicle including altitude, longitude and latitude. At 1208, adetermination is made whether additional waypoints are to be entered. Ifyes, the flow returns to step 1206. If no, the method enters a landingpoint at 1210. The landing point includes the spatial location of thelanding zone. At 1212, a possible flight path is computed. At 1214, adatabases is accessed to determine know obstacles using the possibleflight path. At 1216, the flying weight is determined. At 1218, therelease point from the towing device (e.g., aircraft) is determined.This is based on the flight characteristics of the aerovehicle and thelanding zone location and environment. As 1220, the final flight path isdetermined. At 1222, the final flight path is stored by the controllerin memory accessible to the controller during flight.

FIG. 13 shows a takeoff flight control method 1300. At 1302, the loadsensor senses when the load is lessened and essentially removed from thelanding gear. At 1304, the forward speed of the aerovehicle 100, 1000 issensed. At 1306, the rotational speed of the rotor is sensed. This canbe done at the hub or based on rotation of the drive shaft. At 1308, theangular position of the rotor blades is sensed. The angular position ofthe rotor blades is measured based on the plane that the blades rotatein versus the horizontal plane of the ground or relative to the air flowthat flows against the blades. The angular position has an effect onlift and drag of the aerovehicle. Each of the sensing operationsdescribed with respect to FIG. 13 communicates the sensed data to thecontroller. At 1310, the controller can use the sensed data to controlthe operation of the autogyro assembly including but not limited to therotor rotational speed, the rotor angle, an assist by the prerotormotor, if available, use of the propulsion system, and release of thetow line. The controller can trade altitude for forward speed to createmore lift. The controller can increase the rotor angle to create morelift as long the vehicle stays above a stall speed. The controller canactuate breaks to slow the rotation of the blades to decrease lift.

FIG. 14 shows a landing method 1400. At 1402, the release of theaerovehicle 100 or 1000 from the towing vehicle is sensed. At 1404, theforward airspeed of the aerovehicle is sensed. At 1406, the rotorrotational speed is sensed. At 1408, the rotor angular position issensed. At 1410, the altitude is sensed. This can be sensed by a groundradar or by three dimensional navigational system signals. At 1412, therotor angular position is increased at a first altitude. At 1414, thecontroller can activate the motor to assist the blades in theirrotation. At 1416, the rotor angular position is further increases at aheight close to the ground. At 1418, the load is sensed. At 1420, thebrakes are engaged. The brakes can be rotor brakes to stop the theirrotation. The brakes can also be landing gear brakes to stop rotation ofthe landing gear wheels or brake the landing gear skids.

In an example, the aerovehicle can be released at an altitude of greaterthan 10,000 feet and then automatically using the onboard controller(i.e., unmanned) control its descent to a landing zone. Accordingly, thetow aircraft can remain miles from the landing zone to ensure its safetyif the landing zone is in a military area, particularly where and whenan enemy may be present or consider the target to be of high value. Theaerovehicle, in an embodiment, does not have a running motor during itapproach or landing. Accordingly, the aerovehicle is quiet as it is freefrom motor (e.g., internal combustion or turbine) noise.

While the above examples show the aerovehicle 100 vehicle being towed bya plane, it will be understood that the vehicle can also be towed byother propulsion vehicles e.g., a helicopter. Another example of apropulsion vehicle is a winch that acts on a tow line to move theaerovehicle 100 forward. The tow line can be automatically released oncethe aerovehicle 100 has sufficient forward speed to create lift. Thecontroller can control the release of the tow line. The winch examplewould be useful with the propulsion embodiment as the propulsion systemcan keep the aerovehicle aloft for an extended period relative to thenon-propulsed aerovehicle.

The aerovehicle as described herein includes an autogyro assembly thatprovides for stable low velocity flight. As the rotating airfoil bladesprovide lift and stability, the aerovehicle does not require rollcontrols.

The aerovehicle 100 or 1000 can be used in delivery, military,emergency, and agriculture uses. Agriculture uses can include aerialseeding or aerial spraying. Seed release mechanisms or sprayers can bemounted to the containers 105. The on-board controller can controloperation of the seed release mechanisms or sprayers. The agriculturaluses can further delivery feed to animals. A drop mechanism can bemounted to the containers 105. The drop mechanism can drop an entireload or can drop single units, such as single bales of hay. The on-boardcontroller can control operation of the seed release mechanisms,sprayers, or the drop mechanism.

The present aerovehicle is to be compatible with unmanned aircraftsystem (“UAS”) of the U.S. Department of Defense or the Federal AviationAuthority. The military role of unmanned aircraft systems is growing atunprecedented rates. Unmanned aircraft have flow numerous flight hoursas either drones controlled from a remote location or as autonomousaircraft. The present aerovehicle can be part of a UAS that performsintelligence gathering, surveillance, reconnaissance missions,electronic attack, strike missions, suppression and/or destruction ofenemy air defense, network node or communications relay, combat searchand rescue, and derivations of these themes.

The aerovehicle as described herein operated on the principal of theautogyro and takes advantage of two features of thereof, namely, areduced takeoff and landing area relative to a powered airplanes and,second, its low speed and high speed flight characteristics. In anexample, the aerovehicle as described herein can take off in little aszero fee of runway and in other examples, in less than 50 feet ofrunway. In an example, the aerovehicle as described herein can land inunder twenty feet. Another feature of the aerovehicle is its ability tofly slow and not stall. When the aerovehicle stops its forward motion itslowly settles to the ground as the rotary wing will continue to rotateand create some lift as the aerovehicle settles. In an example, theaerovehicle can fly at speeds as low as 15 mph. This is based on theaerovehicle developing lift with its spinning rotor hub blades. As aresult the aerovehicle has a larger speed envelope. Moreover, thevehicle is capable of flying in a greater range of speeds thanairplanes.

The aerovehicle has the advantage of flying at a low speed without astall. The result of slowing of the aerovehicle down too much is justthat the aircraft will descend gently. Accordingly, the presentaerovehicle has a major advantage over airplanes and helicopters-safetyin event of an engine failure.

The aerovehicle can be used in remote areas, like those in Alaska,Canada, Philippines, and South America. The aerovehicle can be used toprovide supplies, and even fishing boats, to lodges and to remotelocations. Oil and gas exploration and pipeline operations can besupported by aerovehicle delivery. Other applications include mail andparcel delivery, disaster relief, and emergency medical and survivalsupply delivery. The container of the aerovehicle can be modified tohold liquids from fire prevention and can act as a water bombing device.

The aerovehicle further provides some of the hazards of military cargotransport by avoiding ground delivery. Moreover, the aerovehicleincreases the capacity of each flight resulting in fewer flightsrequired to deliver the same amount of cargo. Moreover, the aerovehiclecan deliver cargo where needed with landing the towing vehicle. This issafer for the pilot and ground transport team. The pilot need not landin a hazardous area. The ground transport team need not take the sameroads from the airport to the locations where the equipment is staged orrequired. The aerovehicle can further be delivered in the event ofbrownouts by the use of helicopters, which do not require theelectricity-based assistance that many planes require. The aerovehiclescan be used to stage a forward aerial refueling point. In an example,one aerovehicle can include pumping equipment and any number of tankervehicles can be landed near the pumping vehicle to provide the refuelingpoint.

It will further be noted that the aerovehicle is adaptable to any flyingcraft. As a result, aircraft that are not typically thought of as cargocraft can be used as cargo craft. In an example, a Scout-AttackHelicopter can deliver cargo by towing an aerovehicle as describedherein. Moreover, the helicopter can tow its own support equipment as itdeploys.

The aerovehicle further provides environmental, i.e., “green”, benefitsof reduced fuel consumption and the exhaust products by reducing eitherthe size of the aircraft used to carry a same load or the reduction inthe number of trips required to transport a same amount of cargo. Insome examples, the aerovehicle can reduce fuel use by above 50% for thesame amount of cargo. In certain applications of the aerovehicle 1500,fuel use can be reduced in a range of 70% to 90%. One measure of fueluse is the tonnage of cargo delivered per certain amount of fuel. Insome applications of the aerovehicle 1500, the number of trips requiredby an aircraft are reduced by 75%.

Structures, methods and systems for a towable, unmanned flying vehicleare described herein. Although the present invention is described withreference to specific example embodiments, it will be evident thatvarious modifications and changes may be made to these embodimentswithout departing from the broader spirit and scope of the invention.Accordingly, the specification and drawings are to be regarded in anillustrative rather than a restrictive sense.

The Abstract of the Disclosure is provided to comply with 37 C.F.R.§1.72(b), requiring an abstract that will allow the reader to quicklyascertain the nature of the technical disclosure. It is submitted withthe understanding that it will not be used to interpret or limit thescope or meaning of the claims. All documents referred to in the paperare hereby incorporated by reference for any purpose. However, if anysuch document conflicts with the present application, the presentapplication controls. In addition, in the foregoing DetailedDescription, it can be seen that various features are grouped togetherin a single embodiment for the purpose of streamlining the disclosure.This method of disclosure is not to be interpreted as reflecting anintention that the claimed embodiments require more features than areexpressly recited in each claim. Rather, as the following claimsreflect, inventive subject matter lies in less than all features of asingle disclosed embodiment. Thus the following claims are herebyincorporated into the Detailed Description, with each claim standing onits own as a separate embodiment.

1. An aerovehicle system, comprising: a towing aircraft; a towedaerovehicle; and a tow line releasably connected between the towingaircraft and towed aerovehicle, the towed aerovehicle including; aflight body; an autogyro assembly connected to the flight body; and acontroller to control operation of the autogyro assembly for unmannedflight; wherein, when the controller determines a stall in the towingaircraft, the controller automatically releases the tow line andcontrols the flight of the towed aerovehicle to a landing bysubstantially following a flight path determined by sensed signals and aprogrammed destination.
 2. The aerovehicle system of claim 1, whereinthe autogyro assembly comprises a mast extending from the container, arotatable hub on an end of the mast, and a plurality of blades connectedto the hub.
 3. The aerovehicle system of claim 2, wherein the autogyroassembly comprises a motor to rotate the blades prior to lift off toassist in take-off, and wherein the motor does not have enough power topower the aerovehicle through takeoff absent a further motive force. 4.The aerovehicle system of claim 3, wherein the controller senses forwardmotion in order to control the autogyro assembly.
 5. The aerovehiclesystem of claim 4, wherein the controller receives signals from thetowing aircraft and controls the autogyro assembly using the receivedsignals.
 6. The aerovehicle system of claim 5, wherein the controllercontrols the rotational speed of the hub.
 7. The aerovehicle system ofclaim 2, wherein the autogyro assembly comprises actuators which controlangle of the plurality of airfoil blades, and wherein the controllercontrols the actuators.
 8. The aerovehicle system of claim 1, whereinthe flight body comprises a container to hold cargo, a rear stabilizer,and an undercarriage which supports the container when on the ground. 9.The aerovehicle system of claim 8, wherein the undercarriage includes atrolley that contacts the ground to provide mobility and is removablefrom the container.
 10. The aerovehicle system of claim 1, wherein thecontroller issues control signals to position the airfoil blades fordifferent stages of flight.
 11. The aerovehicle system of claim 10,wherein the controller issues a flight control signal to set the airfoilblades for flight.
 12. The aerovehicle system of claim 11, wherein thecontroller issues a take-off control signal to set the airfoil bladesfor takeoff, wherein the angle of incidence of the airfoil blades isgreater at takeoff than at flight.
 13. The aerovehicle system of claim12, wherein the controller issues a prerotation control signal to setthe airfoil blades for pre-takeoff, wherein the angle of incidence ofthe airfoil blades is greater at takeoff and flight than at prerotation.14. The aerovehicle system of claim 13, wherein the controller issues alanding control signal to set the airfoil blades for landing, whereinthe angle of incidence of the airfoil blades is greatest at landing. 15.The aerovehicle system of claim 14, wherein the controller sets thelanding angle of incidence to 45 degrees or greater and sets the flightangle of incidence to less 30 degrees.
 16. The aerovehicle system ofclaim 1, wherein the controller controls a propulsion system that hassufficient thrust to assist in a cargo laden flight and an essentiallycargo-free flight but does not have enough thrust to fly a flight bodyfull of cargo.
 17. The aerovehicle system of claim 16, wherein thepropulsion system includes an on-board motor, a drive shaft connected tothe motor and extending outside the flight body, and a propellerconnected to the drive shaft.
 18. The aerovehicle system of claim 1,wherein the tow line includes a mechanical component to transfer trustfrom the towing aircraft to the flight body and an electrical componentthat transfers electrical signals from the towing aircraft to thecontroller.
 19. The aerovehicle system of claim 1, wherein thecontroller receives signals from other controllers of nearbyaerovehicles.
 20. The aerovehicle system of claim 19, wherein thecontroller acts as a master controller and issues control signals tonearby aerovehicles.
 21. The aerovehicle system of claim 1, wherein aplurality of aerovehicles are towed by the towing aircraftsimultaneously.
 22. The aerovehicle system of claim 1, wherein theflight body includes sensors that produce signals, and whereincontroller receives the signals and applies instructions to the signalsto output control signals.
 23. The aerovehicle system of claim 22,wherein the sensors include weight sensors on the flight body todetermine at least one of the weight and center of gravity of the flightbody and cargo, and wherein the controller issues a control signal toadjust the position of the autogyro assembly on the flight body.
 24. Theaerovehicle system of claim 23, wherein the controller issues signals tocontrol actuators that adjust a longitudinal position of the autogyroassembly, a lateral position of the autogyro assembly, or both.
 25. Theaerovehicle system of claim 1, wherein the controller receives a forwardair speed indicator to control the speed of the flight body and keepsthe speed below a never-exceed velocity.
 26. The aerovehicle system ofclaim 1, wherein the controller receives a rotation speed signal fromthe autogyro assembly and issues a brake signal if the rotational speedexceeds a safe rotational speed.
 27. The aerovehicle system of claim 1,further comprising a propulsion system and wherein the controllercontrols operation of the propulsion system.